Heat exchanging connector



June 10, 1958 N. D. LARKY ET AL HEAT'EXCHANGING CONNECTOR Filed July 12,1954 INVENTORS Aim y ANKWi/ZIE I irraelfi/ United 2,838,7 40 l-IEATEXCHANGING CONNECTOR Application July 12, 1954, Serial No. 442,498

4 Claims. (Cl. 339-112) This invention relates to heat exchange devices,and particularly to a heat dissipating connector adapted for use withelectron tubes.

It is customary, in the case of electron tubes having external anodesof'high energy dissipation, and where excessive temperatures at an anodeseal vmay result in damage to the'tube, to provide a heat-dissipatingmeans in the form of a separate anode terminal connection or cap.Generally, this anode connection or connector has been made of amaterial which is a good electrical and thermal conductor, such ascopper. The anode connector is often slotted to provide contact fingerswhich are bent inwardly slightly so as to provide a' physical contactbetween the anode and connector.

It has also been the practice to design and construct certain devices,such for example as electron tubes operable at relatively high power,wherein the heat dissipating means is an integral part of the device.Such heat dissip'ating means by virtue of being integrally associatedwith the device, provides better heat dissipation than the separateconnector, but olfers difficulty in the manufacture, and assembly.

Accordingly, it is an object of this invention to provide an improvedheat exchanger such as a removable heat dissipating means, and moreparticularly a heat dissipating means in the form of a separate terminalconnector for ananode, characterized by advantages of good thermal,electrical, and mechanical contact usually associated only with theabove-described integrally constructed form of heat, dissipating means.

In accomplishing this and other objects of the invention, I haveprovided an improved structure, the preferred form of which isillustrated in the accompanying drawing, wherein:

Figure 1 shows a sectional elevation of a heat exchanging anodeconnector according to the invention,

Figure 2 is a sectional view along the line 22 of Figure 1;

Figure 3 is an enlarged view of one contact member or finger of theanode connector shown in Figures 1 and 2;

Figure 4 shows a sectional elevation of a heat exchanging anodeconnector adapted for use with devices having a recess for engaging theheat exchanger; and

FigureS is an enlarged view of one contact member of the anode connectorshown in Figure 4.

In accordance with the embodiment of this invention shown in Figures 1and 2, an integral heat dissipating anode cap is provided having fins 11for radiating and dissipating heat and having at one end a socket 12defined by fingers 13 for receiving a contact pin 14 of an externalanode. If desired, a blast of air or similar cooling medium may bedirected against the fins. An electrical conductor, not shown, may beconnected to the cap 10 and of which the cap 10 may be a terminal. Thecap 10 should preferably occording to. the invention, be constructed ofa material, such as beryllium-copper, which has been heat-treated sothat it will not anneal particu-- rates Patent larly at the fingers 13thereof, at the operating temperatures of the tube but will retain itsflexibility. As will be seen in Figure 2, fingers 13 defining socket 12shown in Figure 1 are disposed in a substantially circular array, so asto contact a substantially continuous annular portion of the tube platepin 14.

When forming the socket 12, a pin, not shown, of somewhat smallerdiameter than the tube plate pin 14 may be placed in the socket, and thecontact fingers then clamped therearound by means of a suitable jig soas to be in intimate contact with the pin. The resultant assembly isthen heat treated, the effect of the heat treating being to release allstrains in the metal of the spring contact fingers 13 at the reducedspacing therebetween.

The contact fingers 13 of the cap are preferably of special shape, asshown in Figure 3. Thus, the contact fingers are undercut as at 15 sothat the diameter of the elongated recess, formed by a plurality offingers 13, is less adjacent its open end than at the inward portionthereof. The extent of the undercut 15 along the length of the fingers13 is preferably about two-thirds of the total length of the fingers 13,the remaining third including a surface 16. The depth of the undercut isrelatively small in relation to the outer diameter of the circularfinger array aforementioned.

In addition, the contact fingers 13 at a portion thereof spaced fromtheir free ends, are undercut or slotted at 17 so that the periphery atsuch undercut portion of the circular array referred to, is smaller thanthe periphery defined by adjacent portions of the fingers to provide arelatively thin portion 18. The depth of this undercut 17 is preferablyless than half the thickness of a contact finger, and the length of theundercut preferably extends along a relatively small portion of thetotal length of a finger.

While the above description has been made with reference to Figures 1,2, and 3 showing a socket of substantially circular shape defined by thefingers aforementioned, so as to provide a substantially continuousannular engagement between the finger array and the tube plate pin 14,it should be understood that the invention is not limited to this. Theinvention may also be embodied in a socket 12 of any shape, such assquare, hexagonal, etc. provided the tube plate pin 14 is ofcorresponding shape.

In describing the operation of the embodiment aforementioned, referencewill be made to Figures 1 and 3..

The surface 16 of each contact member of finger 13 is adapted to bearagainst the tube anode pin 14, as shown in Figure 1, and should be ofsufficient length to provide adequate contact between the finger 13 andtube pin 14. The undercut portion 15 is provided to reduce the thicknessof metal which undergoes bending strain.- Additionally, the slot 17 isprovided in each finger to further reduce the thickness of the finger atthe region of the slot and to further facilitate a bending of thefingers by providing a space into which the metal of the fingers may bedeformed, as shown in the dotted lines of Figure 3. 7

While the reduced thickness of the fingers at the region of slots 17will tend to impede the heat flow through that region-because of itssmaller cross-sectional area, it will be apparent that the temperaturegradient across the region referred to will be relatively large becauseof the temperature difference produced by the relatively cool fins 11 ofcap 10 and the relatively hot anode pin 14 of the tube to be cooled.This temperature difference will tend to cause increased flow of heatacross the thin region 18 and thereby more than compensate fordiminution in heat conductivity resulting from the aforementionedreduction in cross-sectional area. Additionally, heat flow from pin 14to the surface 16 of the fingers 13 is greatly increased by'virtue ofthe improved forced contact provided between that surface and pin 14.There results, therefore, a socket construction which provides improvedthermal and mechanical contact between plate cap 10 and pin 14,increased facility of assembly and disassembly of plate cap 10 withrespect to pin 14, and improved efficiency of heat dissipation from pin14.

Temperature tests were made on an anode cap such as is shown in Figure1, under given operating conditions of a tube having an anode pin 14.The temperature of the cap stabilized at from 65 to 70 C. Similar testswere made on a connector cap of the type previously used and which didnot include the finger structure, including the offset surface 15(Figure 3) and 28 (Figure nor the slot 17 (Figure 1) and 26 (Figure 4),of the invention, nor the gradient in fin diameter shown in Figures 1and 4. In these tests, the tube was operated under the same conditionsas before. The temperature of the prior art connector cap under theseconditions Was in excess of 150 C.

While the foregoing tests provide a comparison between the connector capshown in Figure 1 and a prior art connector cap, in respect of heatdissipating properties, it is believed that a similar comparisonincluding the connector cap 19 of Figure 4 to be described, would revealsubstantially the same advantage of this cap over prior art caps. Thisis because the structure of the connector cap 19 is substantially thesame as that of connector cap 10, as will be explained in the following.

The above-described device is of particular 'value for applicationswherein there is a protruding member such as pin 14 to be inserted intothe device. In addition, there are applications in which it would beadvantageous to provide a heat-dissipating means which would not requirea protruding member on the device to be cooled. Accordingly, a cap inthe form of a plug 19 shown in Figure 4 is provided, having heatdissipating means in the form of fins 20. The plug may be placed in arecessed opening 21 in a device 22, to be cooled as shown fragmentallyin Figure 4. It should be noted that this recessed opening 21 need notbe of any particular shape, and that the shape and form of the sidewalls 23 of this opening need not conform to special design. A simplecircular opening is sufiicient, or the opening may be of square,hexagonal, etc. shape if so desired, provided the plug 19 has a contactportion of corresponding configuration. This contact portion is definedby fingers 24 arranged in a circular array, and having a contactingsurface 25 which forms part of the periphery of the array. inwardly ofthe circular array, each finger 24 is provided with a slot 26 whichresults in a portion 27 of reduced thickness in each finger. Tofacilitate bending response of the fingers 24 the portions thereofextending from surface 25 are undercut as shown at 28 in Figure 5.

It will be noted from the foregoing that the construction of the fingers13 used in the embodiment illustrated in Figures 1 to 3 is essentiallythe same as that of the fingers 24 of the embodiment shown in Figures 4and 5. However, it will be noted that in Figures 1 to 3 the slots 17 arein the outer periphery of the finger array, whereas in Figures 4 and 5the slots 26 are provided internally of the socket defined by thefingers 24. It will be further noted that the contacting surface 25 ofthe fingers shown in Figures 4 and 5 define an outer periphery of thefinger array, whereas the corresponding surfaces 16 shown in Figures 1to 3 constitute a portion of the inner walls of the socket defined bythe fingers.

However, while these differences characterize structure of the fingersforming part of the embodiment of Figures 1 to 3 and the fingers shownin Figures 4 and 5, the functions of the fingers in the two embodimentsare essentially similar. Thus, in each case, the slots 17 and 26 providea space for facilitating a bending of the fingers on mounting on theirrespective associated devices. Furthermore, the surfaces 16 and 25constitute contacting surfaces of the finger array. In addition, theundercut portions 15 and 28 serve to reduce the thickness of the fingersto facilitate bending thereof during the mounting operation.

Furthermore, in each case the finger portions 18 and 27 of reducedthickness provide efficient heat conductivity paths due to the hightemperature gradients between the devices 14 and 22 and the cap 10 andplug 19 resulting from the efficient heat dissipation produced by fins11 and 20.

An additional feature of the aforementioned two embodiments as shown inFigures 1 and 4, involves differences in diameter of the cooling fins 11and 20 on each of these elements. The fins progressively decrease indiameter in the direction of the fingers 13 and 24. The resultantreduction in fin size thus secured in the vicinity of the associateddevice to be cooled causes a reduction of capacity between the fins andcircuit elements of the device to be cooled and thus generally resultsin improved circuit performance, particularly at relatively highfrequencies such as are employed in television broadcast service.

Besides reducing capacity effects as aforementioned, the gradient in findiameter referred to also improves heat dissipation by the cap 10 shownin Figure 1 and plug 19 shown in Figure 4. Thus, each of the fins 11 and20 will have an increased heat dissipating property with increase inspacing from the tube prong 14 and the tube anode 22 to be cooled. Thisis of particular advantage in association with the relatively thickshank of the cap 10 and plug 19 from which the fins extend. Thus, amajor portion of the heat received by the shank adjacent the smaller finwill be transmitted along the shank to the other and larger fins. Theheat so transmitted will be heat received by the shank portionaforementioned and beyond the capacity of the smaller fin to dissipate.The same situation characterizes the remainder of the progressivelylarger fins. Should heat transmitted along the cap or plug shankreferred to and reaching the largest diameter fin, exceed thedissipating capability of this fin, the heat will be returned towardsthe smaller diameter fins, until each fin receives and dissipates a heatquantity related to the total heat quantity received by the cap or plugin the same manner as each fin is related in heat dissipating surfacearea to the other fins. This results in increased efiiciency of heatdissipation. This efficiency is further aided by the taperedconstruction of each fin and by the fact that the progressive reductionin fin diameter provides increased fin areas from which heat radiationis unobstructed by an adjacent fin.

It will be apparent from the foregoing that the invention provides animproved heat dissipating structure that may be utilized advantageouslyin a connector for connection to an anode of an electron tube. Thestructure referred to is characterized by substantially the same heatdissipation as a structure integral with the anode, and yet possessesthe advantage of being separable from the anode, not only for convenientservice as a removable connector, but also for facility in manufacture.

What is claimed is:

1. A terminal connector for an external anode of an electron tube,comprising an integral structure including an elongated shank, aplurality of oppositely disposed fingers extending from one end of saidshank, and a plurality of disc-like fins extending from the sides ofsaid shank and coaxial therewith, said fingers having side surfacesadjacent their free ends adapted to engage said anode and havingtransverse grooves adjacent said shank, said grooves having one group ofwalls defining shoulders on said fingers movable into said grooves onflexure of said fingers in opposite directions, whereby bending of saidfingers in a movement of relatively large magnitude at said grooves isfacilitated for engaging said anode and for urging said side surfacesagainst said anode to 5 provide a forced electrical and mechanicalcontact between said fingers and said anode.

2. A terminal connector adapted to engage an external anode of anelectron tube, comprising an integral structure including an elongatedshank having a plurality of elongated contact members extending from oneend of said shank and defining a closed array and adapted to engage aportion of said anode having surfaces defining an array similar to saidclosed array, said contact members each having a slot extendingtransversely thereof and adjacent said shank for providing reducedcrosssection of said contact members, said slot having a wall defining ashoulder movable into said slot on fiexure of said contact members, toincrease bending resiliency of said members for initiating engagementwith said anode surface, said integral structure including a pluralityof tapered disc-like fins coaxially disposed with respect to andextending from the sides of said shank for efficient heat dissipationfrom said shank, said bending resiliency of said contact membersproviding a force for good heat transfer contact between said contactmember and said anode surfaces, whereby portions of said contact memberson opposite sides of said slots are characterized by a relatively hightemperature difference for increased heat conduction across said reducedcross-section.

3. A terminal connector comprising an integral structure including anelongated shank having a plurality of opposed contact members extendingfrom one end of the said shank, said members having sides adjacent theirfree ends and a region of reduced cross-section adjacent said shank,said members having shoulders adjacent to said region and movable acrosssaid region for increasing the bending resiliency of said members,whereby said sides are adapted to engage in good thermal and electricalcontact in electron tube anode to be cooled and to be connected to acircuit element, said integral structure including a plurality oftapered fins extending from said shank and disposed in a tapered arrayconverging towards said region of reduced cross-section, wherebyportions of said fingers oppositely spaced from said region of reducedcross-section have appreciably difierent temperatures for increasingheat conductivity across said region.

4. A heat dissipating cap adapted to be connected to an electron tubeanode to be cooled, and comprising means extending from one region ofsaid cap adapted to engage said anode in a forced thermal contact, whereby heat is effectively conducted from said anode to said cap, and meansextending from another region of said cap for dissipating the heatconducted to said cap, said last named means comprising a plurality ofspaced round fins coaxially disposed, said fins having tapers convergingtowards their peripheries, said fins being progressively spaced fromsaid one region, the fin closest to said one region having apredetermined diameter, the others of said fins having diametersprogressively larger than said predetermined diameter, wherebyefficiency of heat dissipation from said one region is increased.

References Cited in the file of this patent UNITED STATES PATENTS1,607,346 Heinrich Nov. 16, 1926 1,762,848 Whisler June 10, 19301,913,575 Vollrnar June 13, 1933 2,357,858 Trees et al Sept. 12, 19442,415,404 Baller Feb. 11, 1947 2,446,706 Latimer et a1 Aug. 10, 19482,486,285 Hurst Oct. 25, 1949 2,523,465 Graham Sept. 26, 1950 2,533,483Losquadro Dec. 12, 1950 2,636,067 Kraft Apr. 21, 1953 2,689,337 Burtt etal Sept. 14, 1954 FOREIGN PATENTS 572,161 Great Britain Sept. 25, 1945

